Overview

An Interval Trigger Notification is a local notification that fires repeatedly at a fixed time interval.

It uses UNTimeIntervalNotificationTrigger from the UserNotifications framework with the repeats parameter set to true.

This is commonly used for:

• periodic reminders
• habit tracking notifications
• hydration reminders
• recurring alerts

Example use case:

User taps "Start hourly reminder" → Notification appears every hour.

Notification Flow

Local notifications follow the same scheduling pipeline:

Notification Content
        +
Notification Trigger
        ↓
Notification Request
        ↓
UNUserNotificationCenter
        ↓
Notification delivered

For interval notifications, the key difference is that the trigger repeats automatically.

Key APIs

UNUserNotificationCenter

The system object responsible for managing notifications.

Responsibilities include: